The present invention relates to an improved process for isomerizing cis-2-pentenenitrile to 3-pentenenitriles in the presence of tertiary amines or of amidines as catalysts.
WO-A-05/73176 discloses isomerizing cis-2-pentenenitrile to 3-pentenenitriles with the aid of homogeneously dissolved amines as catalysts, selected from the group of C1- to C20-mono- and diamines.
U.S. Pat. No. 5,070,202 discloses that cis-2-pentenenitrile forms Michael adducts with primary and secondary amines at temperatures of 20 to 200° C.
A disadvantage of these isomerizations is that Michael adducts form from cis-2-pentenenitrile and the amines mentioned as catalysts.